Offshore Wind Farm: Foundation Installed at Anholt, Denmark

Jumbo’s DP2 heavy lift vessel Jumbo Javelin has successfully installed the first Transition Pieces (TPs) for the Anholt Offshore Wind Farm in Denmark. The operation was performed as planned with respect to every detail: transport, installation, accessibility of the TP, grouting and safety. Once again Jumbo proved to have an efficient concept for the transport and installation of wind farm foundations with the use of only one free floating vessel on DP.

After loading the first nine Transition Pieces in Aalborg, Denmark, they were transported to the offshore location. There, the Jumbo Javelin positioned itself on DP next to the pre-installed monopiles and lifted the TPs from her hold onto the monopiles. After leveling the TPs to their final position, the grouting procedure was executed.

Anholt Offshore Wind Farm is being built by DONG Energy. Jumbo is working for the Danish contractor MT Højgaard, who is in charge of installation of the foundations.

Efficient transport and installationThe Jumbo Javelin is able to carry 9 TPs at a time, each with weights up to 200t. All TPs can be stowed vertically in the hold of the vessel for transport to the offshore location. The ship is free floating and uses its DP2 system to create a stable working environment in which TPs can be installed. With two cranes and a high transit speed of up to 17 knots, the vessel is well-equipped for efficient wind farm installation work.

Advantages
Using a DP positioned heavy lift vessel compared to the conventional method of installing TPs brings the following advantages.
- The vessel is used for transporting a considerable load.
- Fast transit to the installation site and fast installation.
- The relocation from one position to the next is a relatively fast one, as the vessel does not need to
reposition anchors or jack up and down again.
- The need of only one vessel for transport and installation.